There are many environments wherein a small compact assembly is desirable. Such high voltage rectifier assemblies should prevent electrical discharge between component parts and should include means for minimizing corona discharge and ozone problems. An example therein is as the assembly to provide a high D.C. voltage, in the range of 8 kv to 35 kv to the focus anode of a TV picture tube.
In various prior art electronic high voltage supplies, the so-called stick rectifier assembly consists of a single solid state rectifier usually in the form of an elongated member with connecting lead wires at either end. As is known, one terminal connects to an A.C. input and the other end connects to the high voltage electrode of the electronic device, for example, a TV picture tube. Prior art stick rectifiers are generally inexpensive; however, the means for mounting the rectifiers in suitable sockets and the means for mounting the socket on the associated chassis requires additional hardware and labor. In certain types of prior art stick rectifier assemblies, the rectifier connects to lead wires and insulative concentric tubing usually of the heat shrinkable type surrounds the lead wires. Preferably several layers of tubing were utilized to provide good dielectric barriers. The assemblies are commonly suspended in spaced relation from ground and lower voltage reference points, such as an associated metal casing, to thereby minimize corona or high voltage breakdown.
Heretofore, in order to reduce expense and hardware, wire leads have been used to make electrical connections as well as for mechanically supporting the rectifier therebetween. The foregoing causes problems, since the rectifier is not securely positioned and any mechanical shift can cause the rectifier to move adjacent to electrical ground, thereby tending to cause high voltage breakdown, ozone problems and other unwanted effects. Transients caused by the foregoing can be radiated into the associated electrical circuits, causing operating and performance problems.
In accordance with the present invention, a rectifier assembly is provided having an improved dielectric spacing between active components while providing good secure positioning of the rectifier assembly for minimizing the problems of high voltage breakdown, corona and ozone. The inventive rectifier assembly is a self-contained, self-mountable unit with high voltage input and output leads. The inventive assembly includes mounting means which are part of the assembly and which are suitably insulated.
The inventive rectifier assembly includes a casing for mounting the components such as the rectifiers, resistors, capacitors and inductors internally thereof. The resistors, for example, can be encapsulated within the casing in series with the input and output leads to provide a low corona connection.
Also, the inventive assembly can be manufactured by insert molding or transfer molding techniques; that is, the components can be initially assembled and then encapsulated by transfer or insert molding techniques.
It is a principal object of the present invention to provide a small, compact, self-mountable, and encapsulated rectifier assembly having an improved high voltage breakdown characteristic.
It is another object of the present invention to provide a small, self-mountable, compact and encapsulated, high voltage rectifier assembly capable of rectifying voltages in the 8 to 35 kv range.
It is still another object of the present invention to provide a high voltage rectifier assembly having uniform high voltage gradient stress throughout the rectifier assembly.
It is another object of the present invention to provide a high voltage rectifier assembly with active or passive components such as diodes, resistors and capacitor mounted in a case and comprising a unitary structure.
It is another object of the present invention to provide a high voltage rectifier assembly providing an improved mechanical mounting means, and improved electrical characteristics for the overall assembly.
The foregoing and other objects, features and advantages of the present invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings wherein: